FULLERTON (CBSLA.com) — A Fullerton couple who married on New Year’s Eve is pleading for the return of a valuable family keepsake lost on their wedding day.

Jessica Sample was honored to wear on her wedding day the prized opal necklace her grandfather gave her grandmother after World War II.

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“When I saw her and I saw her wearing it I knew, I knew exactly what it meant to her,” her husband William said.

The couple held their wedding reception at Disneyland. Shortly after the couple had a caricature made wearing the necklace, Jessica said it disappeared near Blue Bayou in New Orleans Square.

“It’s the most important piece of jewelry in my family, and the fact that I was even allowed to wear it on my wedding day just meant the world to me,” Sample said. “And the fact that I lost it, it just breaks my heart.”

The opal necklace was purchased by the bride’s grandfather in 1944 while stationed in Australia.

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“It’s just such an important piece,” said Jessica. “It just represents their love. I don’t want to lose that.”

Her grandparents’ love survived the war through letters, and lived on long after Jessica’s grandmother lost her husband of 44 years.

When her grandmother began to lose her memory to Alzheimer’s Disease, Jessica said she never forgot her husband.

“She forgot all of us, but she never forgot him, ever,” said Sample.

Sample’s husband William placed an ad on Craigslist, in hopes of making it clear to others that without the story behind it the necklace has little value. He is asking for the necklace back, no questions asked.

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“Sometimes it’s hard to do the right thing when nobody’s looking, but I’m counting on somebody to do that,” he said.